Apparatus for making extracorporeal blood circulation available

ABSTRACT

An apparatus for providing an extracorporeal blood circuit control includes a base module having a control device and a patient module releasably connected to the base module and having blood-conducting components of the extracorporeal blood circuit. A pivot system is also provided at the base module and at the patient module to pivot the patient module relative to the base module about a horizontal axis.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of European Patent Application No.EP 04 027 855.8 filed on Nov. 24, 2004, the disclosure of which isincorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to an apparatus for the provision of anextracorporeal blood circuit, in particular heart-lung machines,comprising at least one base module having a control device and apatient module releasably connected to the base module and havingblood-conducting components of the extracorporeal blood circuit.

BACKGROUND OF THE INVENTION

Heart-lung machines of this type are known, for example, as portabledevices for emergency use. It is a problem in this respect that it mustbe ensured with devices of this type prior to the putting into operationthat there is no longer any air in the blood-conducting components ofthe extracorporeal blood circuit, since this could seriously endanger apatient. A so-called priming liquid is therefore filled in and theextracorporeal blood circuit is vented or deaerated prior to the puttinginto operation in order to eliminate the air bubbles present in theblood-conducting components. This is, however, time-consuming with theknown apparatus.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an apparatus of theinitially named kind with which the venting of a patient module filledwith priming liquid can take place in a short time.

This object is satisfied in particular in that pivot means are providedat the base module and/or at the patient module to pivot the patientmodule relative to the base module about a horizontal axis from afilling position into an operating position.

The patient module can be pivoted in a guided manner relative to thebase module by the pivot means provided in accordance with theinvention, whereby the position and orientation of individual componentsof the extracorporeal blood circuit is modified so that air bubbleswhich cannot escape in the filling position due to the design can beremoved from the system at or after the transition to the operatingposition via venting lines.

The filling and venting of a patent module can take place in a timeperiod in the order of magnitude of approximately 2 minutes due to thepivot means in accordance with the invention, whereas comparableapparatus in accordance with the prior art require approximately 20minutes for this procedure, which can be decisive in emergencysituations.

Advantageous embodiments of the invention are described in thedescription, in the drawing and in the dependent claims.

In accordance with a first advantageous embodiment, there isapproximately 90° between the filling position and the operatingposition, which has the advantage that any air bubbles can reliablyescape from the blood-conducting components.

In accordance with a further advantageous embodiment, a blood reservoiris provided in the patient module and is arranged at an inclination ofapproximately 45° to the horizontal both in the filling position and inthe operating position. This has the consequence that the bloodreservoir again has the same orientation relative to the horizontalafter a rotation of the patient module by 90° so that the same flowconditions result inside the reservoir before and after the pivoting.

In accordance with a further advantageous embodiment, a centrifugal pumphead having a central inlet and a tangential outlet can be arranged inthe patient module such that the inlet is oriented vertically upwardlyin the filling position and horizontally in the operating position. Inthis manner, the pump head can be filled with priming liquid from abovewithout air bubbles remaining in the pump head in this process. It canlikewise be advantageous in this process to provide the centrifugal pumphead with a tangential outlet which is arranged at the bottommostposition of the centrifugal pump head in the operating position. It isensured in this manner that no air is pumped inside the intracorporealblood circuit by the centrifugal pump in operation.

In accordance with a further advantageous embodiment, an arterial filterhaving a venting outlet can be arranged in the patient module such thatthe venting outlet is oriented horizontally in the filling position andvertically upwardly in the operating position. The possibility hereby inturn results that air inside the arterial filter, which is still presentin the filter after the filling with priming liquid, can escape upwardlyvia the venting outlet after a pivoting into the operating position.

The pivot means provided in accordance with the invention can beprovided in the most varied designs and can in particular include amount for the patient module pivotally supported at the base module. Inthis case, the patient module only has to be coupled to the mount inorder to permit a guided pivot movement. It is particularly advantageousin this process for the pivot means to include a guide provided at themount and at the patient module. In this case, the patient module canalso be used to ensure the guided pivot movement.

It is alternatively possible to connect the patient module to a furthermodule, for example to a control module, and to fasten the unit ofpatient module and control module to the mount. In this case, the guidecan be provided at the mount and at the control module.

It is also possible, for example, to provide a pivot bearing at the basemodule into which the other module or other modules are inserted.

The patient module is preferably in the operating position after beingplaced onto the base module since, in this case, a fast removal of thepatient module from the base module is ensured without a pivoting havingto be carried out beforehand.

In accordance with a further advantageous embodiment, the base modulehas a device stand which is provided with a pivotal hook to hang theapparatus on the frame of a patient's bed.

In accordance with a further aspect of the invention, it relates to amethod for the putting into operation of an apparatus of theaforementioned type, with the patient module first being brought intothe filling position in which filling position the blood-conductingcomponents are filled with a priming liquid, with the patient modulesubsequently being pivoted relative to the base module, in particular by90°, into the operating position. The advantages described above resultwith such a method.

In accordance with an advantageous method variant, a pump head providedin the patient module can be driven prior to the pivoting in order topump the already filled-in priming liquid and thereby to further ventthe blood-conducting components.

Further areas of applicability of the present invention will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and specific examples, whileindicating the preferred embodiment of the invention, are intended forpurposes of illustration only and are not intended to limit the scope ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is a perspective view of a portable heart-lung machine;

FIG. 2 is a perspective view of the control module of the heart-lungmachine of FIG. 1 connected to a mount of the base module;

FIG. 3 is a perspective view of some blood-conducting components of thepatient module in the filling position;

FIG. 4 is the representation of FIG. 3 in the operating position, but ina view from the rear; and

FIG.5 is a diagram showing the individual components of the heart-lungmachine.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description of the preferred embodiment(s) is merelyexemplary in nature and is in no way intended to limit the invention,its application, or uses.

The heart-lung machine shown in FIGS. 1 to 4, is composed of threemodules, namely a base module B provided with a device stand 10, acontrol module S and a patient module P which has blood-conductingcomponents of an extracorporeal blood circuit.

In the embodiment shown, the patient module P is coupled via latchelements (not shown) to the control unit S to form a unit and this unit,consisting of the control module S and the patient module P isreleasably latched to a mount 12 of the base module B.

As FIG. 1 shows, the device stand 10 made from tubular material has apivotal hook 14 at its upper side which is bent to form a hook at itsupper side to permit a hanging to a frame of a patient's bed. Thepivotal hook 14 can be pivoted downwardly by 180° from the positionshown in FIG. 1 and can be plugged into two holding clips 16, 17 so thatthe pivotal hook 14 is not in the way on the mounting of the controlmodule S and of the patient module P.

The device stand 10 is fixedly connected to a carrier element 20 of thebase module B which has a plug socket 22 for a mains cable. The mount 12is furthermore pivotally supported in the carrier element 20, as will beexplained in more detail in the following.

An operating part 24 is foldably fastened to the left hand side of thecarrier element 20 in FIG. 1 and has a touch screen 26 which representsan input and output means for a control device (computer) provided inthe base module. As the Figure furthermore shows, the carrier element 20and the non-folded operating part 24 form an annular jacket for the unitof mount 12, control module S and patient module P. The operating part24 must be folded open to the left from the position shown in FIG. 1 tomount or remove the unit of control module S and patient module P.

FIG. 2 shows the mount 12 of the base module B of FIG. 1 to which thecontrol module S is releasably connected by means of latch connections28, 30. The patient module P is not shown in FIG. 2 for a simplifiedrepresentation. It must, however, be pointed out that a unit of controlmodule S and patient module P is always plugged onto or removed from themount 12 in operation.

As FIG. 2 further shows, the control module S supplements thedisk-segment shaped geometry of the mount 12 and a handle 32 is locatedat the upper side of the control module S with which the unit of controlmodule S and patient module P, on the one hand, but also the wholeheart-lung machine, on the other hand, can be handled when the threemodules are fastened to one another as shown in FIG. 1.

To pivot the patient module P only not shown in FIG. 2 relative to thebase module B about a horizontal axis from a filling position into anoperating position, the mount 12 of the base module B is equipped withtwo guide rails 34 which are parallel, provided at the outer peripheryand cooperate with adjoining guide rails 36 of the control module S. Theguide rails 34 and 36 form a continuous guide structure with the aid ofwhich the unit of mount 12, control module S and patient module P can bepivoted relative to the base module B.

As FIG. 2 shows, the guide rails 34 of the pivot mount 12 are providedwith a cut-out 38 with whose aid the pivot mount 12 can be guided overtwo rollers (not shown) provided at the carrier element 20 so that thepivot mount 12 can be pivoted on the support element 20 of the basemodule B. The toothed arrangement recognizable in FIG. 2 serves for theengagement of a damping mechanism ensuring a uniform and damped pivotmovement.

To assemble the pivot mount 12 with the support element 20, the pivotmount 12 is first brought into a substantially vertical position and thecut-outs 38 are guided via the rollers (not shown) provided at thecarrier element 20, whereupon the pivot mount 12 can subsequently bepivoted into the position shown in FIG. 1. After the folding open of theoperating part 24, the previously assembled unit of control module S andpatient module P can be latched on the pivot mount 12. To pivot thepatient module P from the now present operating position into a fillingposition, the now formed unit of control module S, patient module P andpivot mount 12 can be pivoted by 90° by pivoting down the handle 32 sothat the control module S is in the position in which the pivot mount 12was previously located. In this filling position, the blood-conductingcomponents of the patient module P are in the position and orientationshown in FIG. 3 with respect to the horizontal.

FIG. 3 shows some blood-conducting components of the patient module,with the patient module P having been rotated about 90°counterclockwise, starting from FIG. 1. The view shown in FIG. 3corresponds to a view from other side of the patient module P incomparison with FIG. 1. The wall 40 of the patient module P standingperpendicular in FIG. 3 is thus disposed parallel next to the pivotmount 12, whereas the horizontally oriented wall 42 adjoins the controlmodule S. Furthermore, a plurality of hose connections are now shown inFIG. 3 for a better clear view.

In FIG. 3, the reference numeral 44 designates a centrifugal pump headhaving a central suction inlet 46 and a radial outlet 48 shown by brokenlines in FIG. 4.

Furthermore, an approximately parallelepiped shaped blood reservoir 50is installed at a position of 45° in the patient module P and its outlet52 is connected to the inlet 46 of the centrifugal pump head 44 via ahose line (not shown). Venting lines 54 are located at the upper side ofthe blood reservoir 50. The inlet into the blood reservoir 50 comingfrom a venous connection is arranged approximately at the centre of theblood reservoir and cannot be recognized in FIGS. 3 and 4.

Furthermore, it can be recognized in FIGS. 3 and 4 that an arterialfilter 56 is provided in the patient module P which has a cylindricalshape, with a tangential inlet 58 and a central axial outlet 60 beingprovided. A venting connection 62 is provided centrally at the end faceof the filter disposed opposite the outlet 60.

Further components shown of the patient module P are an oxygenator 64and various connection elements which are provided at the wall 42disposed adjacent to the control module S and which serve for thecooperation with terminals, sensors or plug connections, since allblood-conducting components are provided in the patient module P,whereas control components such as the pump drive, valves and otherelectrical control elements are arranged in the control module S.

FIG. 4 shows the representation of FIG. 3 in the operating positionwhich corresponds to the representation of FIG. 1 in which the controlmodule S and the wall 42 of the patient module P contacting it areoriented vertically.

As a comparison of FIGS. 3 and 4 shows, there is 90° between the fillingposition (FIG. 3) and the operating position FIG. 4), with the bloodreservoir 50 provided in the patient module P being arranged in bothpositions at an inclination of 45° to the horizontal, since it isinstalled at 45° in the patient module. The centrifugal pump head 44 isarranged such that the central inlet 46 is oriented vertically upwardlyin the filling position (FIG. 3) and horizontally to the side in theoperating position (FIG. 4). The outlet 48 (not recognizable in FIG. 3)of the pump head 44 is arranged at the bottommost position of thecentrifugal pump head 44 in the operating position shown in FIG. 4 sothat the outlet 48 lies beneath the inlet 46.

The arterial filter 56 is also arranged within the patient module suchthat the venting outlet 62 is oriented horizontally in the fillingposition and vertically upwardly in the operating position (FIG. 4). Theinlet 58 is oriented vertically downwardly in the filling position andhorizontally in the operating position, whereas the outlet 60 isoriented horizontally in the filling position and vertically downwardlyin the operating position.

FIG. 5 shows the different components of the heart-lung machine inaccordance with the invention in which the patient blood coming from avenous connection V is guided via a line 70 into the blood reservoir 50and flows from there via the outlet 52 into the inlet 46 of thecentrifugal pump 44. It is pumped from there via the outlet 48 into theoxygenator 64 and flows from there via the arterial filter 56 to thearterial connection A and from there back into the body of the patient.An internal bypass which can be switched via a valve 72 is designated byreference numeral 71. Reference numeral 73 designates a valve for theinflow line PR with which priming liquid can be guided into the circuit.Reference numerals 74, 75 and 76 each designate pressure sensors.Venting valves are designated by reference numerals 77, 78 and 79, withthe valves 77 and 78 switching the vent paths into the upper region ofthe blood reservoir 50 not filled with blood and the venting valve 79controlling the venting from the blood reservoir. Reference numeral 80designates a bubble sensor which controls a fast-closing valve 82provided in the arterial outlet A if air bubbles are detected. Referencenumeral 84 designates a flow sensor and reference numeral 86 anelectrical interface.

As the Figure furthermore shows, the oxygenator 64 is provided withinflow lines and outflow lines for water and oxygen to effect anenriching of the blood with oxygen and a temperature control of theblood.

To put the heart-lung machine described above into operation, startingfrom the representation of FIG. 1, the pivotal hook 14 is first pivoteddownwardly by 180° and the operating part 24 is folded to the left.Subsequently, the total unit consisting of the control module S, thepatient module P and the pivot mount 12 can be pivoted counterclockwiseso that the filling position is reached.

Priming liquid, which first (cf. FIG. 5) fills the blood reservoir andfrom there the centrifugal pump head 44, is supplied via the connectionPR in the filling position. The air located in the hosing is largelyremoved from the system in this process by the priming liquid arrangedabove the machine on filling, with air bubbles, however, remaining inthe upper region of the arterial filter 56 and in horizontal lineportions.

When the blood reservoir 50 is almost filled, the centrifugal pump head44 is set into rotation comparatively slowly, whereby the priming liquidis pumped through the system and further air residues are removed fromthe system. After a time period of approximately 20 seconds, furthercomponents—such as the oxygenator 64—are also filled with priming liquidso that the pump can be stopped and the unit of the control module S,patient module P and pivot mount 12 can be pivoted back into theoperating position. After these pivoting back by 90°, that air can alsoescape which had remained in the arterial filter 56 and in horizontalline portions. A complete filling and venting of the patient module canthus be achieved within a time period in the order of magnitude ofapproximately 2 minutes.

The description of the invention is merely exemplary in nature and,thus, variations that do not depart from the gist of the invention areintended to be within the scope of the invention. Such variations arenot to be regarded as a departure from the spirit and scope of theinvention.

1. An apparatus for providing an extracorporeal blood circuit, inparticular a heart-lung machine, comprising: at least one base modulehaving a control device; a patient module releasably connected to thebase module and having blood-conducting components of the extracorporealblood circuit; and pivot means that are provided at one of the basemodule and the patient module for pivoting the patient module relativeto the base module about a horizontal axis from a filling position intoan operating position.
 2. An apparatus in accordance with claim 1,wherein an angular range of approximately 90° is defined between thefilling position and the operating position.
 3. An apparatus inaccordance with claim 1, further comprising a blood reservoir that isprovided in the patient module which is arranged at an inclination ofapproximately 45° to the horizontal in the filling position and in theoperating position.
 4. An apparatus in accordance with claim 1, furthercomprising a centrifugal pump head having a central inlet and atangential outlet and that is arranged in the patient module such thatthe inlet is oriented vertically upwardly in the filling position andhorizontally in the operating position.
 5. An apparatus in accordancewith claim 1, further comprising a centrifugal pump head having atangential outlet and that is arranged in the patient module such thatthe outlet is arranged at the bottommost position of the centrifugalpump head in the operating position.
 6. An apparatus in accordance withclaim 1, further comprising an arterial filter having a venting outletand that is arranged in the patient module such that the venting outletis oriented horizontally in the filling position and vertically upwardlyin the operating position.
 7. An apparatus in accordance with claim 1,wherein the pivot means includes a mount for the patient modulepivotally supported at the base module.
 8. An apparatus in accordancewith claim 7, wherein the pivot means includes a guide which is providedat the mount and at the patient module and/or at a further moduleconnected to the patient module.
 9. An apparatus in accordance withclaim 1, wherein the patient module is in the operating position aftermounting onto the base module.
 10. An apparatus in accordance with claim1, wherein the base module has a device stand which is provided with apivotal hook to hang the apparatus to the frame of a patient's bed. 11.A method for implementing an apparatus that provides an extracorporealblood circuit, in particular of a heart-lung machine, comprising atleast one base module having a control device and a patient modulereleasably connected to the base module and comprising blood-conductingcomponents of the extracorporeal blood circuit, with pivot means beingprovided at the base module and/or at the patient module for pivotingthe patient module relative to the base module about a horizontal axisfrom a filling position into an operating position, the methodcomprising: bringing the patient module into the filling position;filling the blood-conducting components with a priming liquid in saidfilling position; and pivoting the patient module into the operatingposition relative to the base module, in particular by 90°.
 12. A methodin accordance with claim 11, further comprising driving a pump head ofthe patient module prior to the pivoting to vent the blood-conductingcomponents.